26 



AGRICULTURAL BACTERIOLOGY. 



the successive divisions follow one another in the same plane. 

 If the spheres break away from each other after division, sepa- 

 rate spheres, of course, arise, but it frequently happens that they 

 remain clinging together for a time after division, so that long 

 chains are produced (Fig. 6, a). In other cocci the second divi- 



Fio. 6. 



r> 

 







\ V) 



Cocci or spherical bacteria : a, Streptococcus ; b t Micrococcus ; c, Sarcina. 



sion plane is at right angles to the first (Fig. 6, b\ In these 

 cases, if the spheres remain attached they form irregular 

 masses (Fig. 6, b). In a third type the divisions are in the three 

 planes of space at right angles to each other (Fig. 6, c). In 

 such cases there result solid masses of fours or some mul- 

 tiples of four. In accordance with these methods of division 

 the cocci are divided as follows : 



Streptococcus. Division in one plane only, commonly form- 

 ing chains (Fig. 6, a). 



Micrococcus. Divisions in two planes, the spheres either sep- 

 arate or forming irregular masses (Fig. 6, b). When forming 

 masses they are sometimes called Staphylococcus and when in 



